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72. Merizocotyle euzeti sp. n. (Monogenea: Monocotylidae) from the nasal tissue of three deep sea skates (Rajidae) in the southwestern Atlantic Ocean
- Creator:
- Irigoitia, Manuel M., Cantatore, Delfina M. P., Delpiani, Gabriela E., Incorvaia, Inés S., Lanfranchi, Ana L., and Timi, Juan T.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- taxonomy, monogeneans, host specificity, Amblyraja doellojuradoi, Bathyraja brachyurops, Zearaja chilensis, and Argentina
- Language:
- English
- Description:
- A new species of Merizocotyle Cerfontaine, 1894 (Monogenea: Monocotylidae) is described from the nasal tissues of three deep sea rajid skates: the southern thorny skate, Amblyraja doellojuradoi (Pozzi), broadnose skate, Bathyraja brachyurops (Fowler), and yellownose skate, Zearaja chilensis (Guichenot), collected off Buenos Aires Province, Argentina, southwest Atlantic Ocean. Two additional species of sympatric rajid, the white-dotted skate, Bathyraja albomaculata (Norman), and the Patagonian skate, Bathyraja macloviana (Norman), were also examined but no merizocotylines were found. The taxonomy of the Merizocotylinae is not widely accepted and, as a result, the status of Thaumatocotyle and Mycteronastes, and their proposed synonymy with Merizocotyle are currently under discussion. The new species differs from its congeners by having a unique haptoral structure, 6 peripheral loculi that are asymmetrically arranged (one much smaller, indistinctly located in the left or right side of the haptor). The presence of the new species in three sympatric species of Rajidae belonging to distinct genera and subfamilies, as well as its absence in sympatric congenerics indicates the lack of phylogenetic host specificity. Host ecology and geographical distribution appear to be more important than host phylogeny in determining the distribution of this parasite across potential hosts in the region. This constitutes the first record of Merizocotyle in the southwestern Atlantic Ocean.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
73. Mitochondrial DNA variation in Tibetan macaque (Macaca thibetana)
- Creator:
- Sun, Binghua, Li, Jinhua, Zhu, Yong, and Xia, Dongpo
- Type:
- article and TEXT
- Subject:
- phylogeny, subspecies, and taxonomy
- Language:
- English
- Description:
- Tibetan macaques (Macaca thibetana) are a threatened primate species endemic to China. The current taxonomy of the species is based on external morphological and anatomical variations. To further understand the intraspecific variation and relationships among populations, we analyzed 44 mitochondrial DNA control region sequences (475 bp fragment) from individuals across the species range. Results revealed 11 major haplotypes with a high nucleotide diversity (0.792), but nucleotide diversity within haplotype lineages was only 0.042. Neighbor-joining phylogenetic analyses indicated support for four distinct haplotype clades corresponding to regional groups consistent with the recognized subspecies M .t. thibetana, M. t. guizhonensis, M. t. huangshanensis and M. t. pullus. As a result of regional geographic variation and genetic differences, we recommend the four subspecies should be considered different management units for conservation efforts.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/
74. Molecular phylogeny of the Microsporidia: ecological, ultrastructural and taxonomic considerations
- Creator:
- Vossbrinck, Charles R. and Debrunner-Vossbrinck, Bettina A.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Microsporidia, phylogeny, taxonomy, classification, and systematics
- Language:
- English
- Description:
- The Microsporidia are a group of obligate intracellular parasites, now thought to be derived fungi. Presented here is a comparative small subunit rDNA (ssrDNA) analysis of 125 species of Microsporidia (sequences obtained from GenBank). This analysis shows that groups or clades are formed based largely on habitat and host. This result is supported by comparative molecular analyses of the past decade, and indicates that structural and ultrastructural characters are unreliable for distinguishing among higher-level microsporidian taxa. Our findings indicate the presence of five major clades of Microsporidia which group according to habitat. We present three new classes of Microsporidia based on natural phylogenetic groupings as illustrated by the ssrDNA analysis: Aquasporidia, Marinosporidia and Terresporidia. The names of the proposed classes reflect the habitat of each group. The class Aquasporidia, found primarily in freshwater habitats, is a paraphyletic group consisting of three clades. The Marinosporidia are found in hosts of marine origin and the Terresporidia are primarily from terrestrial environments.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
75. Monogenoidean parasites of freshwater stingrays (Rajiformes: Potamotrygonidae) from the Negro River, Amazon, Brazil: species of Potamotrygonocotyle (Monocotylidae) and Paraheteronchocotyle (Hexabothriidae)
- Creator:
- Domingues, Marcus V., Pancera, Norberto C. M., and Marques, Fernando P. L.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Monogenoidea, Monocotylidae, Hexabothriidae, Potamotrygonocotyle, Paraheteronchocotyle, Potamotrygonidae, taxonomy, Amazon, Negro River, and Brazil
- Language:
- English
- Description:
- Five new species of Potamotrygonocotyle (Monocotylidae) are described and Paraheteronchocotyle amazonense Mayes, Brooks et Thorson, 1981 (Hexabothriidae) is redescribed from monogenoideans collected on the gills of species of Potamotrygonidae from the Negro River, Amazon, Brazil. Potamotrygonocotyle quadracotyle sp. n. and P. umbella sp. n. were found parasitizing an undescribed species of Potamotrygon; Potamotrygonocotyle rarum sp. n. is described from Potamotrygon schroederi; Potamotrygonocotyle rionegrense inhabits Potamotrygon cf. motoro; Potamotrygonocotyle aramasae sp. n. is a parasite of Paratrygon aiereba; and Paraheteronchocotyle amazonense is reported from Potamotrygon orbignyi. The diagnosis of Paraheteronchocotyle is emended, and P. amazonense is redescribed.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
76. Morphological comparison of bleaks (Alburns, Cyprinidae) from the Adriatic Basin with the description of a new species
- Creator:
- Buj, Ivana, Vukić, Jasna, Šanda, Radek, Perea, Silvia, Ćaleta, Marko, Marčić, Zoran, Bogut, Ivan, Povž, Meta, and Mrakovčić, Milorad
- Type:
- article and TEXT
- Subject:
- taxonomy, east Adriatic Basin, and Neretva River basin
- Language:
- English
- Description:
- The morphometric, meristic and phenotypical characters of the members of the genus Alburnus from the Adriatic Basin were analyzed on specimens from 11 localities, representing eight watersheds. The number of gill rakers, the number of lateral line scales, the number of branched anal fi n rays and the coverage of the ventral keel by scales have the greatest signifi cance in differentiating between species. Signifi cant morphological differences exist between the Alburnus population from Lake Lugano (type locality for Alborella maxima Fatio, 1882) and all the remaining investigated populations. Alburnus from the Neretva River drainage is described as a new species and it is distinguished from other species of the genus Alburnus by the following combination of characters: 131/2-151/2 branched anal fi n rays; 17-26 gill rakers; 40-48 lateral line scales; fi rst anal fi n ray below branched dorsal rays 6-10 or located up to one scale after the last dorsal fi n ray; ventral keel exposed for at least 2/3 of a distance between the pelvic fi n base and the anal aperture. The status of the Neretva River basin populations as a separate species was corroborated by genetic analyses, with p-distance between newly described species and A. arborella from the Zrmanja River 1.8-2.2%.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/
77. Morphological description and molecular characterisation of Dactylogyrus matlopong sp. n. (Monogenea: Dactylogyridae) from the South African endemic Labeobarbus aeneus (Cyprinidae: Torinae)
- Creator:
- Acosta, Aline A., Truter, Marliese, Malherbe, Wynand, and Smit, Nico J.
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- yellowfish, new species, taxonomy, ribosomal genes, and ITS1 region
- Language:
- English
- Description:
- Dactylogyrus Diesing, 1850 is the most species-rich genus in Platyhelminthes, with over 900 documented species, that are mostly strictly specific to freshwater cyprinoids. The morphological Dactylogyrus groups afrobarbae-type, carpathicus-type, pseudoanchoratus-type, and varicorhini-type are known to occur in Africa. This study describes a new species of Dactylogyrus of the varicorhini-type from the gills of the endemic smallmouth yellowfish Labeobarbus aeneus (Burchell) from the Vaal River, Free State Province, South Africa. Dactylogyrus matlopong sp. n. is unique among its varicorhini-type congeners mainly by the accessory piece of the male copulatory complex that presents a hook-shaped subunit with defined round base not reaching the male copulatory organ, combined with the presence of a conspicuous medial projection on the anterior margin of the ventral bar. Sequences of the partial 28S and 18S rRNA genes, together with entire ITS1 region, were generated for the first time for a species of Dactylogyrus from South Africa. Concatenated phylogenetic analyses of selected Dactylogyrus spp. showed that these parasites group according to their morphological types.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
78. Morphology and taxonomy of Stomylotrema (Digenea: Stomylotrematidae) representatives from ciconiiform and podicipediform birds in Cuba
- Creator:
- Macko, Josef Kazimír, Špakulová, Marta, and Casanova, Juan Carlos
- Format:
- Type:
- model:internalpart and TEXT
- Subject:
- digenetic trematodes, Stomylotrema bijugum, Stomylotrema vicarium, Cuba, variability, taxonomy, Ajaia ajaja, Egretta caerulea, and Podiceps dominicus dominicus
- Language:
- English
- Description:
- Two Stomylotrema Looss, 1900 species were found in storks and grebes in Cuba. Five specimens of Stomylotrema bijugum Braun, 1901 were recovered from the roseate spoonbill, Ajaia ajaja (Allen, 1942) (Ciconiiformes) while six Stomylotrema vicarium Braun, 1901 were found in the little blue heron, Egretta (syn. Florida) caerulea (L.) (Ciconiiformes) and the least grebe Podiceps dominicus dominicus (I,.) (Podicipediformes). The taxa represent new host and geographical records. The problem of morphological variation within the genus Stomylotrema is briefly analysed in the discussion.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
79. Morphology of the karyologically identified spined loach (Teleostei, Cobitidae) from a diploid population
- Creator:
- Jeleń, Iwona, Boroń, Alicja, Szlachciak, Jolanta, and Juchno, Dorota
- Type:
- article and TEXT
- Subject:
- diploids, Cobitis taenia, morphology, osteology, and taxonomy
- Language:
- English
- Description:
- The variability of morphological characters was studied in a population of spined loach from Klawój Lake karyologically identified as a pure diploid C. taenia (2n = 48). 24 metric features were used to calculate correlation coefficients and linear regressions to determine the relationships between metric features with total length. As regards 11 meristic features, females had more lateral and predorsal spots than males. Statistically significant differences between males and females were also found in mean values of 15 metric indices. Age variability in the shape of the lamina circularis of males was revealed.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/
80. Morphology, homogonic development, and lack of a free-living generation in Strongyloides robustus (Nematoda, Rhabditoidea), a parasite of North American sciurids
- Creator:
- Bartlett, C. M.
- Format:
- Type:
- model:internalpart and TEXT
- Subject:
- Strongyloides robustus, nematode, taxonomy, morphology, homogonic development, free-living generation, sciurids, and red squirrels
- Language:
- English
- Description:
- Adult females of Strongyloides robustus Chandler, 1942, a parasite of sciurids in North America, were found in the duodenal mucosa of 30 of 32 red squirrels (Tamiasciurus hudsonicus (Erxleben)) collected in Cape Breton Island, Nova Scotia, Canada. The parasitic female is illustrated and redescribed; characteristics include: body 3.8-8.0 mm long, cephalic extremity with X-shaped mouth and 8 circumoral lobes, ovaries spiralling around intestine, and tail bluntly rounded. Eggs in fresh feces contained tadpole-stage larvae. In fecal cultures, eggs hatched and larvae invariably developed to the filariform infective third stage; i.e. a free-living generation did not occur and is probably absent in S. robustus in Cape Breton and possibly other parts of North America. It is hypothesized that homogonically developing S. robustus might be more fecund or more efficiently transmitted than species of Strongyloides that exhibit both homogonic and heterogonic development. Larvae of S. robustus in fecal cultures, i.e. homogonic larvae, are described in detail. Intestinal walls of second- and third-stage larvae, as well as the lateral chords of young third-stage larvae, contained numerous round bodies, likely nutrient stores. Third-stage larvae were present within 2 days in cultures maintained at 30°C, 4 days at 20°C, and 7 days at 15°C. They lived for at least 33 and 30 days at 15° and 20"C, respectively. Third-stage larvae probably die when their nutrient stores are exhausted.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public